2019/04/09 by Samuel Brem, August Ekman, Dominik Christiansen +10 · 1 citation
Chemistry · Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Chemistry #Condensed matter physics #Dephasing #Exciton #MXene and MAX Phase Materials #Materials science #Molecular physics #Monolayer #Nanotechnology #Optics #Optoelectronics #Perovskite Materials and Applications #Phonon #Photoluminescence #Physics #Spontaneous emission #Transition metal #Tungsten #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1021/acs.nanolett.0c00633
published as Nano Lett. 2020, 20, 4, 2849-2856
arxiv created 2019/04/09 · openalex publication_date 2020/02/21 · arxiv updated 2020/04/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
High Resolution Image Download MS PowerPoint Slide The photoluminescence (PL) spectrum of transition-metal dichalcogenides (TMDs) shows a multitude of emission peaks below the bright exciton line, and not all of them have been explained yet. Here, we study the emission traces of phonon-assisted recombinations of indirect excitons. To this end, we develop a microscopic theory describing simultaneous exciton, phonon, and photon interaction and including consistent many-particle dephasing. We explain the drastically different PL below the bright exciton in tungsten- and molybdenum-based materials as the result of different configurations of bright and momentum-dark states. In good agreement with experiments, our calculations predict that WSe 2 exhibits clearly visible low-temperature PL signals stemming from the phonon-assisted recombination of momentum-dark K–K′ excitons.